Numbers 10:9-10

New American Standard Bible

⁹ And when you go to war in your land against the enemy who ^(A)attacks you, then you shall sound an alarm with the trumpets, so that you will be ^(B)thought of by the Lord your God, and be saved from your enemies. ¹⁰ Also on the day of your joy and at your appointed ^[a]feasts, and on the first days of your months, ^(C)you shall blow the trumpets over your burnt offerings, and over the sacrifices of your peace offerings; and they shall be as a reminder of you before your God. I am the Lord your God.”